OptiFine 1.4.4 Mod farview can extend your viewing distance up to a factor of 3, which is excellent if you need to grab a distant view of a particular object or landmark for whatever reason. You can tweak the night and day settings to allow infinite day or night. And of the coolest options by far is OptiFine clear water setting. This will allow you to see underwater for miles which is especially useful on some of the maps mods that feature really deep water.